GRIDFORM™ is a prefabricated fiber reinforced polymer (FRP) double-layer grating, concrete-reinforcing system with integral stay-in-place (SIP) form for vehicular bridge decks.
System Design and Components
GRIDFORM™ consists of two layers of pultruded FRP I-bar grating separated by FRP connectors with nylon bolts. The grating features standard I-bars on 4” centers and cross rods on 4” spacings. A 1/8” pultruded FRP plate is bonded to the bottom grating layer to create a stay-in-place concrete form.
This system creates a bidirectional, lightweight panel for the grid construction of corrosion-free concrete bridge decks.
The lightweight GRIDFORM™ panel, which weighs only 4.7 pounds per square foot, is shop-fabricated in very large units that are limited only by shipping constraints to approximately 50 ft. by 8 ft.
When the GRIDFORM™ arrives on site, it is lifted with a single pick of a crane and placed directly in the bridge girders. The GRIDFORM™ panel is pre-engineered and detailed to enable rapid attachment to the bridge girders and subsequent concrete placement and forming.
The anticipated lifespan of a GRIDFORM™ bridge deck is several times that of steel reinforced concrete bridge decks since FRP provides a corrosion-free reinforcement system for the concrete.
GRIDFORM™ makes headlines!
Click here to read an article from the August 2006 issue of Composites Manufacturing magazine, which contains an in-depth feature on a recent GRIDFORM™ installation in Greene County, Missouri.
History of GRIDFORM™
Strongwell began developing the GRIDFORM™ system with the University of Wisconsin in 2001.
First generation of the GRIDFORM™ system was installed on a bridge in Waupun, Wisconsin, in 2003.
Second generation of the GRIDFORM™ system was installed on a vehicular bridge near Fond du Lac, Wisconsin, by the Wisconsin Department of Transportation in 2004. The Fond du Lac research project compared two bridges: one constructed using the GRIDFORM™ system and another constructed with conventional steel rebar reinforcement.
Third generation of the GRIDFORM™ system was installed on a vehicular bridge in Greene County, Missouri, in 2005. A 1/8” thick FRP plate was integrated into the system and bonded to the bottom layer of grating to create the stay-in-place concrete form.
GRIDFORM™ Design Guide
The GRIDFORM™ Design Guide is provided as a service to structural engineers to determine if GRIDFORM™ can be used as an alternative to steel rebar as the internal reinforcement system for reinforced concrete bridge decks. The use of GRIDFORM™ by an engineering firm or installation contractor is governed by Strongwell's Terms and Conditions of Strongwell Web Site Use. Please review these terms and conditions prior to using the GRIDFORM™ Design Guide.
The GRIDFORM™ Design Guide requires Microsoft® Excel® version 2003 or 2007.
SAFSTRIP® is a pultruded composite strip that improves the strength of an existing structural member when mechanically fastened to the structure.
The reinforcing strip has high bearing and longitudinal properties and is designed to strengthen the flexural capacity on the tension face of concrete girders, slabs and decks. Installation on bridges can occur without any interruption of service.
Features of SAFSTRIP®
Easy to install, no skilled labor necessary
Minimal surface preparation is needed for installation
Structure is usable immediately after installation
Cost effective system for increasing load capacity of bridges
Will not split or delaminate when drilled
Materials of Construction
SAFSTRIP® is composed of carbon tows sandwiched between layers of fiberglass mats and rovings. The materials are bonded together by a highly corrosion resistant vinyl ester resin. Carbon fibers increase the stiffness of the strip while glass mat provides the proper bearing strength. These combined properties allow SAFSTRIP® to be mechanically attached to a structural member. A synthetic surfacing veil is also incorporated into the composite to improve resistance to corrosion and UV degradation.
SAFSTRIP® Design Guide
The SAFSTRIP® Design Guide is provided as a service to structural engineers to determine if SAFSTRIP® is a product that can be used to economically rehabilitate deteriorated concrete structures. The use of SAFSTRIP® by an engineering firm or installation contractor is governed by Strongwell's Terms and Conditions of Strongwell Web Site Use. Please review these terms and conditions prior to using the SAFSTRIP® Design Guide.
The SAFSTRIP® Design Guide requires Microsoft® Excel® version 2003 or 2007.